By: Dr. Amjad Hammad
Retinal detachments can be pretty frightening. Often, I don’t get to see a patient soon enough as most hope the symptoms will “just go away.” Basically, the earlier I can diagnose and manage a retinal detachment, the better chance of doing well.
If not treated promptly a retinal detachment can result in permanent vision loss. A detachment occurs when the retina is lifted or pulled from its normal position in the eye. It may begin with a small tear or break that leads to a full detachment. It is extremely important to recognize that a retinal detachment is a medical emergency and should be treated as one.
Signs of a detachment or tear include a sudden or gradual increase in floaters or specks that float in your field of vision. It may also begin with a curtain over the field of vision.
There are three different types of retinal detachment:
Rhegmatogenous [reg-ma-TAH-jenous] – A tear or break in the retina allows fluid to get under the retina and separate it from the retinal pigment epithelium (RPE), the pigmented cell layer that nourishes the retina. These types of retinal detachments are the most common.
Tractional - In this type of detachment, scar tissue on the retina’s surface contracts and causes the retina to separate from the RPE. This type of detachment is less common.
Exudative – In this type, fluid leaks into the area underneath the retina, but there are no tears or breaks in the retina. Frequently caused by retinal diseases, including inflammatory disorders and injury/trauma to the eye.
Causes and Risk Factors
A detached retina usually stems from a retinal tear or retinal hole. Occasionally there is a history of trauma. Retinal detachments usually happen in normal, healthy individuals. Surgery is required in most cases and is about 90-95% successful in reattaching the retina. Visual return is dependent upon age, length of detachment and involvement of the macula.
A retinal detachment can occur at any age, but it is more common in people over age 40. It affects men more than women, and Whites more than African Americans.
A retinal detachment is also more likely to occur in people who:
- Are extremely nearsighted
- Have had a retinal detachment in the other eye
- Have a family history of retinal detachment
- Have had cataract surgery
- Have other eye diseases or disorders, such as retinoschisis, uveitis, degenerative myopia, or lattice degeneration
- Have had an eye injury
Symptoms and Detection
Symptoms include a sudden or gradual increase in either the number of floaters, which are little “cobwebs” or specks that float about in your field of vision, and/or light flashes in the eye. Another symptom is the appearance of a curtain over the field of vision. A retinal detachment is a medical emergency. Anyone experiencing the symptoms of a retinal detachment should see an eye care professional immediately.
The natural course of a retinal detachment is blindness. On rare occasion, with time, there may be loss of the eye. So there really isn’t much choice, but to operate in an attempt to repair the detached retina. Surgery for a retinal detachment is usually urgent. The timing and urgency of surgery depends upon the macula. If the macula is attached (the best situation), surgery may be scheduled before the macula becomes detached. If the macula is already detached (central vision is now reduced or absent), the timing is less imperative. This sounds a bit counter-intuitive I know.
Small holes and tears are treated with laser surgery or a freeze treatment called cryopexy. During laser surgery tiny burns are made around the hole to “weld” the retina back into place. Cryopexy freezes the area around the hole and helps reattach the retina.
Retinal detachments are treated with surgery involving a vitrectomy or a scleral buckle, or both.
During a scleral buckle, a tiny synthetic band is attached to the outside of the eyeball to gently push the wall of the eye against the detached retina. If necessary, a vitrectomy may also be performed.
During a vitrectomy, the doctor makes tiny incisions in the sclera (white of the eye). Next, a small instrument is placed into the eye to remove the vitreous, a gel-like substance that fills the center of the eye and helps the eye maintain a round shape. Gas is often injected to into the eye to replace the vitreous and reattach the retina; the gas pushes the retina back against the wall of the eye. During the healing process, the eye makes fluid that gradually replaces the gas and fills the eye.
I will discuss having a vitrectomy in more detail in Chapter 6.
With modern therapy, over 90 percent of those with a retinal detachment can be successfully treated, although sometimes a second or third surgery is needed. However, the visual outcome is not always predictable. The final visual result may not be known for up to several months following surgery. Even under the best of circumstances, and even after multiple attempts at repair, treatment sometimes fails and vision may eventually be lost. Visual results are best if the retinal detachment is repaired before the macula (the center region of the retina responsible for fine, detailed vision) detaches. That is why it is important to contact an eye care professional immediately if you see a sudden or gradual increase in the number of floaters and/or light flashes, or a dark curtain over the field of vision.